Olefine containing pkoduct



Jan. .27, 1931. v H. s. DAvls ET Al.

OLEFIE CONTAINING PRODUCT Filed Feb. 24. 1927 2 sheets-sheet 1 Jan. 27, 1,931. H. s. DAVIS E1' AL .Y 1,790,522

OLEFINE CONTAINING PRODUCT Filed Feb. 24, 1927 2 Sheets-Sheet 2 meme .im 21,1931

UNITED STATES PATENT our-lcs- HAROLD S. DAVIS, F vBELMONT, AND WALLACE J'. MURRAY, `Oll READING, MASSA;- CEUSETTS, ASSIGNOBS, BY MESNE ASSIGNMENTS, .TO PETROLEUM CHEMICAL COB- POBATION, OF NEW YORK, N.Y., A. CORPORATION 0F DELAWARE OLEFINE CONTAINING PRODUCT Application led February 24', 1927, Serial No. 170,631, and in Germany February 23, 1984?.A

This invention relates to the preparation, segregation and utilization of oleiine hydro- -carbons and to the production of their derivay tives, including alcohols and other useful substances. The olefines may be derived from such materials as petroleum, peat, coal, oil shales, and like carboniferousnatural materials by cracking or. pyrogenesis, so called.

The olefine mixtures produced by heating such substances to degrees resulting in pyrogenetic transformations are, as well known, exceedingly complex, generally containing ethylene, propylene, butylene, amylenes, hexylenes and higher olenes of the general formula C.. 2n. Unlike saturated hydrocarbons, olefines are capable of readily reacting or combining with reagents, including the polybasic' acids (of which sulfuric acid or phosphoric acid are typical) the halogens and halogen compounds, hypocholorous and other acids. f

Olenes when reacted upon by acids are capable of forming alkyl acid reaction prodl ucts, and in turn these alkyl acid products may be hydrolyzed for conversioneinto alcohols of structural characteristics according to the different structures of the base (olene) materials. For reasons fully set out in our application'for Letters Patent for Preparation of olene derivatives, filed February 24, 1925, Serial No.10,992, an acid treatment of the Whole material produced by cracking for the optimum conversion of the natural hydrocarbons to olefines is undesirable because of A :.25 the various degrees of reactivity of components of the mixture produced by the most effective type of heat treatment for cracking of the natural hydrocarbons; for example cracking b the process disclosed and claimed 4o in the app ica-tion for Letters Patent by Earl P. Stevenson and- Clarence K. Reiman liled February 13, 1925, Serial No. 8,907, which discloses a process comprising as steps subjecting the vapors of a petroleum or a frac.-

tional distillate of petroleum,- such as gas -rich gases, s'uch as result from vapor phase ly divergent, and to produce themV in admixture during a relatively long timeof-low, this constant temperature being such as to result in optimum development of olene values; for example, as the result of treatment at a substantially constant temperature of a selected value between 600 C. and 650 C. during a sufficient time of iioW to produce from 1000 to 1700 cubic feet of gaseous prod- Auct per barrel of 42 gallons passed. When -the olefine bearing gas is rich in highly re-' active oleines, a single-stage treatment to obtain acid products can not be practiced; the reaction of the more highly reactive olefnes and other hydrocarbons to form polymers upon treatment with acids capable of forming addition compounds with the less reactive olefnes is too vigorous and too pro' '65 ductive of heat to permit this even in the case of relatively lean gases.

If it were practicable to obtain mixed alkyl acid compounds and 'other derivatives of the cracking directed to the production of olenes, by a group reaction with acid, the re sult would not be desirable. The different alcohols, at least eight in number, resulting from hydrolysis of the obtainable compounds have'boiling points ranging from 80o to 140 C., and separation from each other is in most cases not feasible. The uses of these alcohols (e. g. isopropyl and amyl alcohols) are wideture would be commercially undesirable.

This .inventionprovides certain olene bearing products, compositions or mixtures capable of improved utilization in the production of derivatives, for example secondary and tertiary alcohols. The new products claimed may be regarded in one aspect as progressive simplifications of a type of eliiux mixture of products of a preferred kind of vapor-phase cracking of suitable hydrocartracted from a more complex mixture; or of the materials from which or process by which the composition of matter or its ingredients may be compounded, or synthesised from hydrocarbons of other structures; or of the modes or processes of making derivatives in or for which the new material is of particular utility.

It will therefore be understood that mention of the source materials from which said composition of matter is derived or the process by which it is derived is informative only of the best mode known to us of making or compounding the said composition of matter, and except as expressed in the claims the source materials or the mode of preparation or mode of use hereinafter explained is not explained as a limitation of the invention.

One recommended procedure comprises a stage or stages of separation of a fraction or fractions of the material containing the oleine or olefine group to be recovered, followed by treatment selectively to differentiate and segregate the component olefine substances in accordance with their respective and relative chemical reactivities.

In the accompanying drawings,y

Fig. 1 is a diagrammatic flow sheet of one form of apparatus in which cracking of a suitable hydrocarbon followed by stages of separation of the elux material to arrive at a product and a simplified product according to this invention may be carried out 5 and Fig. 2 is a simplified diagram also illustrating stages of the productlon of the products herein claimed.

Referring to Fig. 1, a container 1 for the supply of oil may deliver to a feed stock reservoir 2, whence by a suitable pressure device P the material is forced into a preheater or primary vaporizer 4 (preferably a 'suitable tubular coil) and through a superheater or secondary vaporizer 6, which may be substantially the same kind of tubular heater as the primary preheater 4. Between the preheater 4 andsuperheater 6 the flowing stream,

through a pipe 6 and a cooler C to tar storage tanks 10.

Vapors superheated at 6 pass to a cracking tube 7. The efiluent gases, vapors and suspensions from cracking are recommended to be treated in a separator 8, which may work on the Cyclonic or centrifugal principle, and deliver its liquids into the pipe 6a, and its vaporous and gaseous efllux into the bottom of the first of a series of separating and condensing towers, for example, the tower 11, adapted to countercurrent flow in contact of the vapors and gases and the condensate from tower 12, which in turn is 'adapted to countercurrent flow of the vapors and gases and the condensate from a fractionating condenser 13 of any suitable reflux type. v.

The tower 12 is preferably a fractionating tower of the bubble type. From the bottom is taken a relatively heavy fraction which is` delivered into the top of tower 11, wherein it serves to condense and wash out any heavy and undesirable tars formed in the cracking reaction. From one of the lower plates of this tower is drawn off a fraction of substantially the same boiling range as the feed stock, but as this will, of necessity, contain some hydrocarbons in the motor spirit range, it can not be returned to the feed stock without materially decreasing the yield of motor spirit. Provision is included, therefore, for stripping this fraction of-its lighter hydrocarbons, such as a fractionating tower 12, which is heated at the base at 14and delivers overhead the desired fraction of its feed into one of the top plates of tower l2. The stripped cycle stock is delivered through a pipe 14a and cooler C to the feed stock tank. The overhead from 13 is cooled at 18, and

the condensate at this point isy crude motor spirit in the preferred operation of tower 12.

The vaporous eihuent from condenser 18 is now fractionally condensed or absorbed, or otherwise treated to separate out a fraction or fractions of the olefines, which from their preponderant contents, may be described as an amylenel and butylene fraction, and a gaseous fraction rich in propylene and ethylene. For example, the stripped gaseous eliiuent from condenser 18, a simplified product not herein claimed, may be separately collected or may be delivered through meter M.

It will be observed that the fraction or extract of the` oleine-rich vapor phase eillux collected or flowing at M has been deprived of condensible tars at 5 and 8; that oil vapors of a boiling-point range comparable with the material in 2 have been`condensed and removedwat 12; and that volatiles in the gasoline boiling-point range have been condensed and removed at 18; for example, contents boiling at higher points than about 100 C. have beenv substantially removed. The material at M is therefore a suitablematerial as lCO a starting point for the conversionof its high percentage (in excess-of 50%) of valuable olefin'e contents b chemical treatment without complication y inclusions higher boiling than the amylenes.v As more fully explained in said application Serial No. 10,992, 'further division and simplification of the mixed vaporous and gaseous product atM is desirable.

For example, this material is now scrubbed in absorption towers 20 and 21 by a countercurrent liow of cool absorption oil stored in a tank 23, delivered Iby a pump P through a cooler C2 and pipe 24 to thetop of tower 21, to

receiver 25, pumped at 1:2 througha cooler C? to the top of tower20,'and the saturated oil delivered through a pipe 26 to a stora etank 27, whence the saturated oil may flow t rough a heat exchanger 28, pipe still 29 and vaporizer 30 to a reuxing tower31, fromwhich the liquids may be led through cooler C* to the crude motor-spirit or gasoline storage tank 16 by pipe 32. Unvaporized absorption oil from va orizer 30 may ilow through pipe 30,

heat exc anger 28, cooler Cs to `tank 23.

The vapors eiiluent at 33 may be delivered through a condenser 34 and a separator 35.,

whence the vapors. pass to a compressor 36 and pressure storage tank 37. Condensates Y at 34, and 37; may be delivered-to tankl 17,

the pressures and temperatures being' such as to provide at these points liquid fractions corresponding to the amylene-fraction fluid in tank 17. Pressure tank 37 may deliver, if" desired, through asuitable reduction valve to gas-holde`r 40, in which are collectedy the lresidual gases from the saturated scrubbing oil. This gaseous fraction,.`if so separated, represents substantially the major portion of the butylene hydrocarbons, whereas the residual gas from tower 21, collected in the holder '22, contains the propylene and etlylenetthe hydrogen, methane, ethane and other gases of low molecular weight.

When appro riateconditions are realized in and prior to ow through the cracking tube 7 the respective fractions capable of being separated by steps of condensation or absorption are sharply characterized by the desired preponderance (amounting under good conditions to substantial freedom from mixture with each other) of the olefine substances sought tovbe collected and separated. Any y suitable condensation or absorption fractionating treatment may therefore beresorted to, and the apparatus mentioned may be varied in accordance with engineering. preferences.

By proper control -of the temperature of the absorption oil and rate of ilow of the va- 'porous and gaseous material from `M, the operation is to cause a selective'absorptlonln 20, 21 of amylenes and butylenes and their associated dioleiines and delivery toholder 22 ofgases of the boilin point of propylene (.48.4 C.) and loweroiling points is readily eifected.

. By roper control of the temperature at 34 and o the rate and degree of compression at 36, and because of the hivh absorptive ainity of liquid amylenes (boi 1n'g`range from 21"A I to42 C. at normal pressures) forthe bu lenes (boilin range from 6- C. to`1 the amylene liquid may be caused to absorb substantially all of the butylenes as liquids, and to hold these substances in solution at -ordinary temperatures under moderate superimposed pressures, for example from twenty to eighty pounds above atmos heric Y pressure. As more fully explained in t e ap'- plication for Letters Patent of Harold S. Davis Serial No. 43,208, filed July 13, 1925, the liquid form of this amylene-butylene mixture has value incidental to subsequent chemical treatment of the contents of this oleline liquid. Associated with the amylenes and butylenes are substantial inclusions of diolefines, believed to be butadienes, isoprene, and

Conversions per bbl. passed per' hour per six4 inch.

Process gus (sp. gr. 1.055) at M 1035 ru. ft. Oil scrubbed gas (sp, gr. 0.929) at 22 675 cu. ft Butylone fraction (non-condensed gas from distillation of saturated absorption oils) (sp. gin-1.52) 102 ru. ff, Amylene fraction (condonsables recovered by fractonatipn to 60 C.) 2. 6 gallons Crudo naphtha (condensubles between 60 and 210 C.) 9. 3 gallons Cyclo stock (condcnsables above 210 C.) 19 gallons Tar residues 2. 1 gallons Olefine content of gaseous fractions Process gas per cent olenes above ethylene 33.1 Oil scrubbed gas per cent oletlnes above ethylene 17. l Butylene fraction per cent oleines above ethylene 75. 7

The oleiine contents ,of the gases received practice with quanllU at 22 and the pressure liquid received at 17, Y

arranged inversely in thelr order of reactivity with sulfuric acid are.:

incassa Butene-land butene-2 are secondary-base olenes which reactl to give the same secondary alcohol on treatment with an absorbing Boiling points State 1. Ethylene CH2=CH2 103 C. Gas 2. Propylene CH3 CH=CH2 48.5 C. Gas 3. Pentene-l CH8 CH2 CH2 CH=CH2 S29-40 C. Liquid 4. Pentene-2 CH8CH2CH=CHCH8 36 C. (741 mm.) Liquid 5. Butene-l CH8 CH2 CH=CH2 5 C. Gas or in solution `6. Butene-2 CHBCH=CHH3 i1 C. Gas or in solution 7. lsopropyl ethylene CH3 l CH CH- CH CH2 21.1 C. Liquid i l 3 8. Unsymmetrical methyl ethyl CH3 ethylene C CH2 31 to 33 C. Liquid 9. Trimethyl ethylene CH3\ @H3 37 to 42 C. Liquid 02s,/ n l0. lso-butylene @H3 o=ori2 6 e. eas or in CH3 solution The liquid at 17 may also contain- 11. Hexylenes, boiling range 55 C. to 7 5 C.

12. Higher oleines, boiling range te 150 C.

and not more than and generally much less than 20 per centuin of hydrocarbons of other series such as the parafiins.

The amylene-butylene liquid at 17 thus comprises a cracked distillate of petroleum boiling under 100 C., containing not less than eighty per eentum and generally more than ninety per eentum of unsaturated hydrocarbons (hexylenes, amylenes, butylenes, diolefines) having as a group characteristic capacity to be polymerized by strong sulfuric acid, the liquid having a vapor pressure at 25 C. in excess of lthe pressure of 760 mm. of mercury. ln other Words, this liquid begins to boil at normal atmospheric temperatures and pressures, but at any usual temperatures remains a liquid at pressures of twenty to seventy pounds per square inch above atmospheric pressure.

The gases at 22 comprise another oleine mixture containing the propylene and ethylene of the gaseous efflux at M as Well as the methane, ethane, hydrogen .and other loW-atomic-Weight gases not absorbed by the oil absorption treatment. Typically this mixed gas has a specific gravity of 0.929, and by volume comprises over 0.675 of the material at M.

The amylene-butylene liquid at 17 'is a starting-point material valuable for the con- Venient derivation by chemical treatment of the tertiary and secondary butyl and tertiary `and .secondary amyl alcoholsv by several available modes of treatment, as Well as fory a source of other derivatives of thecontained olefines.

acid and hydrolysis, Whereas iso-butylene is a tertiary-base olefine which reacts on acid absorption and the addition of Water to a itertiary alcohol having the structure CH3 OH CH3 ein lso-butylene being very greatly more reactive'to absorption acids than buteue-l or butene-Z, a preferential reaction With a weaker acid is available to extract this substance and the highly reactive dioleines i' rom the association with secondary base olefines reacting to secondary alcohols.

rl`he amylene oleiines are oi so nearly the same order of reactivity to absorption acids as to enable a group extraction of iso-butylene and tertiary base amylene oleiines, by absorption in either sulfuric acid of appropriate concentration (about 65%, for example) or treatment with hydrochloric arid. After this extraction, the secondary-base butylene andl amyleneremainders are in condition for treatment with stronger acid, `for example sulfuric acid of 77% 0r greater concentration.

Recoveries severally of tertiary butyl .and amyl alcohols, and recoveries severally of secondary butyl and amyl alcohols from the oleine-acid products by hydrolysis and distillation are possible, the several alcohols of each of these groups having a sufficient differentiation of boiling points to enable their separation by reetifying distillation, or alternatively, the isomeric butylenes and ainylenes can be separately recovered and treated for the production of alcohols.

' As more fully explained in our said application Serial No. 10,992, thc fraction contain'- ing the butylenes, butene-l, butene-2 and isobutylene, which substances collectively have a boiling-point range :from-5 C. to lf C.

may be permitted ou decrease-ofpressure .to

distill from its solution in the amylene liquid, or, alternatively, may be separated from the cold and compression stages 34, 37' Without having been dissolved, and thence collected at 40. It will be observed that this fraction is a fraction of the pressure liquid ofamylenes and butyleues in solution collected at 17, and this butylene product 'may' be'col- .lected in any suitable pressure tank at 40 for separate use, if desired.

The butylene fraction may be treated as a gas or kept as a liquid by superimposed pressure. If separation'o the butylene fraction l containing butene-1, lontane-2, and isobutylene is resorted to, as it may be whether or not the butylenes are dissolved in the amylene liquid, the butylene fraction may be v passed as indicated at 50, Fig. 2, through sulfurie acid of a concentration of 60% more or less in such a manner as to effect as intimate contact as possible, for the purpose of vse- 30 lectively absorbing isobutylene, and removing the tertiary alkyl acid product from the secondary-baseolenes, butene-l and butene-y 2, which as a product maybe collected at 55. One of the advantages of this procedure arises from having removed the isobutylene reacting to tertiary compounds since the reaction with the secondary-alcoholforming substances with stronger acid for their conversion causes heating of lesser degrec, and the natural rise of temperature, for example to C., may be permitted to take place on treatment of the materiall at 55, unless acid more concentrated than 80% is resorted to, in which case it may be desirable to hold the temperature down to a point. below 15 C.

e claim 1. Thev olefne containing fraction ofcracked hydrocarbon 'substances 4substantially as described cbntaining more Y than eighty per centum of unsaturated hydro- 3. The oleine containing fraction of cracked petroleum containing in excess of eighty per centum of unsaturated hydro-V carbons of the boiling point ranges from 6. C. to 100 C. at atmospheric pressures and principally comprised of the amylenes and butylenes.'v l

4. The herein described hydrocarbon liquid' containing amylenes, butylenes, and other unsaturated hydrocarbons, and substantially free from oleflnes of lower boiling v points than 6 C. and of any inclusion of higher boiling point than 100 C. at atmospheric pressures.

Signed by us at Boston, 'assachusetts, this 23rd day of February, 1927.

HAROLD S. DAVIS. WALLACE J. MURRAY.

.'carbons including amylenes and butylenes,

and substantially free of inclusions of-ca'rbon compounds of lesser molecular `weights 55 than ropylene. i

2. e olefine containing fraction of' cracked hydrocarbon substances substantially as described containing -more than eighty per centum of unsaturated hydrocarbons including amylenes andA butylenes, and substantially free of inclusions of carbon compounds of lesser atomic weights than proylene, and substantially free of inclusions 5 eures.

Boiling above 100 C.- at atmospheric pres- 

